Pregnant cow nutrition and its effects on foetal weight – a meta-analysis

Abstract

The prenatal development of cattle has influence on productive performance throughout postnatal life. The number of muscle and fat cells that the animal will have throughout its life is determined in the foetal stage and is influenced by nutrition of the pregnant cow. A systematic review and meta-analysis was performed to evaluate the effect of different energy levels (total digestible nutrient, TDN) and crude protein (CP) supplied to pregnant cows on foetal weight at 4 (FW4) and 8 months (FW8) and calf birth weight (CBW). Four studies and six trials involving 170 animals were assessed for FW4; four studies, four trials and 156 animals for FW8 and 48 studies, 125 trials and 9053 animals for CBW. High heterogeneity across studies was presented in FW4 (I2 = 94.4%), FW8 (I2 = 91.08%) and CBW (I2 = 96.9%). Dietary TDN and CP levels did not influence FW4. The FW8 was reduced by 2.24 kg when cows were fed 100% of their CP and TDN requirements (I2 = 0%), relative to those fed 70% of their requirements during the first and second trimesters. The CBW was reduced by 0.45 kg (I2 = 96.9%) when cows were fed 130% of their CP requirements relative to other dietary CP levels. When cows were fed 140% of their TDN requirements, CBW decreased by 2.71 kg (I2 = 98.3%) relative to other TDN levels. Dietary energy or CP levels fed above the requirements to pregnant cows restrict foetal development and CBW.

Pregnant beef cow’s nutrition and its effects on postnatal weight and carcass quality of their progeny

“…Similar groups of animals subjected to the same treatment with or without intervention were considered as comparative groups. This study continues the data already published [14] about weight of fetuses and calves, however, in this study the outcomes of interest were progeny body weight at 60 (BW60), 100 (BW100), 180 (BW180) and 205 (BW205) days of age; average daily gain (ADG) in the finishing period to slaughter; age, weight, loin eye area (LEA), marbling and fat thickness (FT) at slaughter. To be relevant to our SR, the studies should include at least one of the outcomes of interest.…”

“…To be relevant to our SR, the studies should include at least one of the outcomes of interest. A search protocol was developed, and each screening tool was adapted from forms applied in earlier studies [ 14 – 16 ]. The protocol was tested before being implemented.…”

“…Overfeeding of pregnant cows can increase fat thickness, finishing degree, and carcass yield on slaughter of their progeny [7], i.e., it improves adipogenesis without compromising fetal myogenesis [4]. However, energy oversupply can be detrimental to fetal development, leading to low birth weight [14]. Conversely, maternal malnutrition has been reported to reduce the fetal loin eye area and calf weight at 105 days of age [12].…”

Prenhez ao abate em fêmeas bovinas de descarte

“…O fato dessas vacas não emprenharem na estação monta e serem descartadas pode estar relacionado pelo déficit energético sofrido nesse período, ou seja, o animal não consegue ingerir o alimento suficiente para manter suas funções reprodutivas (Zago;Canozzi;Barcellos, 2019), ou ainda pela ocorrência de problemas sanitários (Alfieri;Alfieri, 2017;Lopes et al, 2017). Convém salientar, ter o aumento de fêmeas abatidas reflexos no mercado de bezerros dos próximos anos, devido o menor número de nascimentos de bezerros (Gonçalves et al, 2017).…”

Ante-Natal and Post-Natal Influences on Neonatal Immunity, Growth and Puberty of Calves—A Review

“…Recently, considering the interactions between these vital physiological processes has become important to optimize calf survival. During gestation, the placenta supports foetal development and prepares it for extra-uterine survival [ 1 ]. After birth, colostrum transfers immune molecules [ 2 , 3 ] which, in case of failure, causes increased susceptibility to infections that lowers survival [ 4 , 5 ].…”